Comma butterfly

📖Overview

Polygonia c-album (the Comma) is a medium-sized anglewing butterfly known for its deeply scalloped wing margins and cryptic underside that resembles a dead leaf. Adults are often seen sunning on warm days at woodland edges, hedgerows and gardens. The species typically has two or more broods per year in temperate regions and overwinters as an adult, sheltered in leaf litter, bark crevices or buildings.

Females lay eggs singly on the leaves of several common host plants. Caterpillars feed on the undersides of leaves until pupating; older caterpillars have a white patch on the back that makes them look like a bird dropping; adults feed on nectar, sap runs and overripe fruit. The Comma is not dangerous to people and is valued by gardeners as a pollinator and as part of local biodiversity.

🔍How to identify a comma butterfly

Wings are irregularly scalloped with a 'torn' outline. Upperwings are orange-brown with darker mottling and small dark spots; forewing and hindwing margins often have dark borders. The underside is mottled brown to dark brown and highly cryptic, closely resembling a dead leaf; the hindwing underside bears a small, distinct white mark shaped like a 'C' or a short curved line, which gives the species its common name. Size and contrast of markings vary regionally and between seasonal forms (a paler, brighter early-summer form called hutchinsoni develops quickly and breeds the same year, while the darker form overwinters).

1. Look for the small white C-shaped mark on the underside of the hindwing - the key field mark.
2. Deeply scalloped, ragged wing margins giving an 'anglewing' outline.
3. Upperwings orange-brown with darker mottling; underside cryptic brown resembling a dead leaf.
4. When at rest with wings closed, silhouette and leaf-like underside help separate it from more rounded butterflies.

Lookalikes

↻Life cycle

1. 🥚

   Egg

   Females lay eggs singly on the upper surface or edges of host plant leaves. Eggs hatch in about 1-2 weeks depending on temperature.

2. 🐛

   Larva (caterpillar)

   Spiny caterpillars, orange-brown to black with a large white patch on the rear half that makes them resemble a bird dropping, feed on the undersides of host leaves; they go through several instars over 2-6 weeks.

3. 🫛

   Pupa (chrysalis)

   Pupation usually occurs attached to stems or leaves; the chrysalis stage lasts about 1-3 weeks before the adult emerges.

4. 🦋

   Adult

   Winged adults feed on nectar, tree sap, dung and overripe fruit; they may produce two or more broods per year and adults of the final brood enter hibernation.

🍃Diet and predators

🌱Effect on plants and gardens

Caterpillars feed on a range of host plants including stinging nettle (Urtica dioica), currants and gooseberries (Ribes species), hops (Humulus lupulus), elm (Ulmus) and other local shrubs; feeding is usually localised and rarely causes serious damage.

📍Where and when to find it

Adults: sunny perches, woodland rides, hedgerows, garden fences and tree trunks. Eggs and larvae: undersides of host plant leaves (nettles, Ribes, hops). Pupae: attached to stems or leaf underside.

✨Fun facts

• The Comma's cryptic underside makes it one of the best-camouflaged butterflies; it often looks exactly like a curled dead leaf.
• Adults hibernate over winter and can be among the first butterflies seen on warm days in late winter or early spring.
• The species has two forms: a paler early-summer form (hutchinsoni) that breeds the same year, and a darker form that hibernates through winter.

?Frequently asked questions

📷Photos of the comma butterfly